Dexamethasone Inhibits Mucous Glycoprotein Secretion via a Phospholipase A₂ -Dependent Mechanism in Cultured Chinchilla Middle Ear Epithelial Cells

Jizhen Lin Otitis Media Research Center, University of Minnesota School of Medicine, Minneapolis, MN, 55455, USA; Department of Otolaryngology, University of Minnesota School of Medicine, Minneapolis, MN, 55455, USACorrespondence[email protected]

Steven K. Juhn Otitis Media Research Center, University of Minnesota School of Medicine, Minneapolis, MN, 55455, USA; Department of Otolaryngology, University of Minnesota School of Medicine, Minneapolis, MN, 55455, USA

George L. Adams Otitis Media Research Center, University of Minnesota School of Medicine, Minneapolis, MN, 55455, USA; Department of Otolaryngology, University of Minnesota School of Medicine, Minneapolis, MN, 55455, USA

G. Scott Giebink Department of Otolaryngology, University of Minnesota School of Medicine, Minneapolis, MN, 55455, USA; Department of Pediatrics, University of Minnesota School of Medicine, Minneapolis, MN, 55455, USA; Otitis Media Research Center, University of Minnesota School of Medicine, Minneapolis, MN, 55455, USA

Youngki Kim Department of Otolaryngology, University of Minnesota School of Medicine, Minneapolis, MN, 55455, USA

Abstract

Lin J, Juhn SK, Adams GL, Giebink GS, Kim Y. Dexamethasone inhibits mucous glycoprotein secretion via a phospholipase A2-dependent mechanism in cultured Chinchilla middle ear epithelial cells. Acta Otolaryngol (Stockh) 1997; 117: 406-413.

Inhibition or attenuation of mucous hypersecretion in middle ear epithelium is a key step toward resolution of mucoid otitis media. Mucous hypersecretion induced by platelet-activating factor (PAF) in cultured Chinchilla middle ear epithelial cells is dependent on arachidonic acid metabolites via PAF receptors, suggestive of the role of phospholipase A₂ (PLA₂) in mucous glycoprotein (MGP) secretion. In this study, dexamethasone added to cultured Chinchilla middle ear epithelial cells inhibited baseline and PAF-induced MGP secretion in a concentration-dependent manner. A definite time lag (16 h) was observed between administration of dexamethasone and MGP inhibition. This inhibition was reversed by the addition of exogenous PLA, (the rate-limiting enzyme of arachidonic acid metabolism) and actinomycin D (an inhibitor of mRNA synthesis). This suggests that dexamethasone inhibits baseline and PAF-induced MGP secretion via a PLA₂-dependent mechanism.

Key Words:

Reprints and Corporate Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

To request a reprint or corporate permissions for this article, please click on the relevant link below:

Order Reprints Request Corporate Permissions

Academic Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

Obtain permissions instantly via Rightslink by clicking on the button below:

Request Academic Permissions

If you are unable to obtain permissions via Rightslink, please complete and submit this Permissions form. For more information, please visit our Permissions help page.

Related Research Data

The role of inflammatory mediators in the pathogenesis of otitis media and sequelae.

Source: Korean Society of Otorhinolaryngology-Head and Neck Surgery

Linking provided by

Dexamethasone Inhibits Mucous Glycoprotein Secretion via a Phospholipase A₂ -Dependent Mechanism in Cultured Chinchilla Middle Ear Epithelial Cells

Related Research Data

Information for

Open access

Opportunities

Help and information

Dexamethasone Inhibits Mucous Glycoprotein Secretion via a Phospholipase A2 -Dependent Mechanism in Cultured Chinchilla Middle Ear Epithelial Cells

Abstract

Reprints and Corporate Permissions

Academic Permissions

Related Research Data

Related research

To cite this article:

Download citation

Information for

Open access

Opportunities

Help and information

Keep up to date

Your download is now in progress and you may close this window

Login or register to access this feature

Dexamethasone Inhibits Mucous Glycoprotein Secretion via a Phospholipase A₂ -Dependent Mechanism in Cultured Chinchilla Middle Ear Epithelial Cells